A perchlorate oxidizing agent. Rubidium perchlorate as chosen because its precipitation provides an excellent separation from strontium and since it is also an accepted weighing form for rubidium.
This Thermo Scientific Chemicals brand product was originally part of the Alfa Aesar product portfolio. Some documentation and label information may refer to the legacy brand. The original Alfa Aesar product / item code or SKU reference has not changed as a part of the brand transition to Thermo Scientific Chemicals.